1Agroscope,Tioleyre 4,1725 Posieux,Switzerland.
Animal. 2019 May;13(5):950-958. doi: 10.1017/S1751731118002495. Epub 2018 Oct 16.
Mineral composition and relative deposition rates in the pig's body are used to assess the mineral net requirements for growth and input-output balances. The study aimed to examine the dynamics of changes in mineral composition and deposition rates in the empty body (EB) from birth to 140 kg BW depending on dietary protein supply. In the experiment, 66 entire male, 58 castrated and 66 female Swiss Large White pigs were used to determine body composition at birth, 10, 20 kg and at 20 kg intervals from 40 to 140 kg BW. From 20 kg BW, they had either ad libitum access to a control grower and finisher diet or a grower and finisher diet containing 80% CP, lysine, methione+cystine, threonine and tryptophan of the control diet. Each EB fraction (carcass, organs and empty intestines, blood and bile) was weighed and analyzed for water, ash, calcium, phosphorous, magnesium, potassium, sodium, copper, iron, manganese and zinc contents. Allometric relationships between the amount of each mineral in the EB and the EB weight (EBW) were fitted. The R2 of the allometric equations was above 0.92, except for copper and manganese (below 0.33), revealing the EBW as an excellent explanatory variable of the analyzed amounts. The copper and manganese composition in the EB were extremely low and variable which explain the low R2. Except for zinc, all mineral relative deposition rates decreased with increasing EBW. The amount of ash, calcium and phosphorus in the EB was not affected by the diet, but when expressed relative to body protein these minerals were increased when pigs were fed the low protein diet. This suggests an independent protein deposition and bone mineralization when animals are fed diets limiting in protein content. The diet also affected the amount of potassium in the EB which was greater when the low protein diet was fed. The gender only affected the amounts of potassium and sodium in the EB which were greater in entire males. Entire males had also greater amounts of water in the EB, which may explain the observed effect of gender on these two electrolytes. Finally, gender and dietary protein did not affect to a sufficient relevant way the body mineral composition and deposition rates in the EB, suggesting that their distinction may not be necessary to assess, on BW basis, the mineral net requirements for growth and the exported amount of minerals in input-output balances.
猪体的矿物组成和相对沉积率用于评估生长的矿物净需求和投入-产出平衡。本研究旨在研究不同蛋白质供应条件下，从出生到 140 公斤体重时，空体（EB）中矿物组成和沉积率的变化动态。在实验中，使用 66 头全雄、58 头去势和 66 头雌性瑞士大白猪，分别在出生时、10 公斤、20 公斤和 40 公斤至 140 公斤体重时，每隔 20 公斤体重，自由采食对照生长育肥猪日粮或含有对照日粮 80%粗蛋白、赖氨酸、蛋氨酸+胱氨酸、苏氨酸和色氨酸的生长育肥猪日粮。对每个 EB 部分（胴体、器官和空肠、血液和胆汁）进行称重和分析，以测定水分、灰分、钙、磷、镁、钾、钠、铜、铁、锰和锌含量。拟合 EB 中每种矿物质的含量与 EB 体重（EBW）之间的异速关系。所有异速方程的 R2 均高于 0.92，除铜和锰（低于 0.33）外，表明 EBW 是分析量的极好解释变量。EB 中的铜和锰含量极低且变化较大，这解释了低 R2。除锌外，所有矿物质的相对沉积率均随 EBW 的增加而降低。日粮对 EB 中的灰分、钙和磷含量没有影响，但当以体蛋白表示时，用低蛋白日粮饲养的猪体蛋白含量增加。这表明当动物采食蛋白质含量有限的日粮时，存在独立的蛋白质沉积和骨矿化。日粮还影响 EB 中钾的含量，当饲喂低蛋白日粮时，钾的含量更高。性别仅影响 EB 中钾和钠的含量，全雄猪的含量更高。全雄猪的 EB 中水分含量也更高，这可能解释了性别对这两种电解质的影响。最后，性别和日粮蛋白质对 EB 中矿物质组成和沉积率的影响没有达到足够的相关程度，表明在基于 BW 的基础上，它们的区分可能不是评估生长的矿物净需求和投入-产出平衡中矿物质输出量所必需的。
